Hearing aids are portable hearing devices which serve to assist the hard of hearing. In order to meet the numerous individual needs, different designs of hearing aid are provided, such as behind-the-ear (BTE) hearing aids, hearing aids with external microphones (RIC: receiver in the canal), and in-the-ear (ITE) hearing aids, including for example concha hearing aids or canal hearing aids (ITC, CIC). The hearing aids itemized by way of example are worn on the outer ear or in the auditory canal. In addition however, bone conduction hearing aids, implantable or vibrotactile hearing aids are also available on the market. These effect stimulation of the damaged hearing either mechanically or electrically.
In principle hearing aids have as their essential components an input transducer, an amplifier and an output transducer. The input transducer is generally a sound receiver, e.g. a microphone, and/or an electromagnetic receiver, e.g. an induction coil. The output transducer is mostly realized as an electro-acoustic transducer, e.g. a miniature loudspeaker, or as an electromechanical transducer, e.g. a bone conduction hearing aid. The amplifier is commonly integrated into a signal processing unit. This constructional principle is shown in FIG. 1 by the example of a behind-the-ear hearing aid. A hearing aid housing 1 for wearing behind the ear has built into it one or more microphones 2 for receiving the sound from the environment. A signal processing unit 3, which is also integrated into the hearing aid housing 1, processes the microphone signals and amplifies them. The output signal from the signal processing unit 3 is transmitted to a loudspeaker or earphone 4 which outputs an acoustic signal. The sound is, if necessary, transmitted via a sound tube, which is fixed in the auditory canal with an otoplastic, to the device wearer's eardrum. The power supply for the hearing aid and in particular that for the signal processing unit 3 is provided by a battery 5 which is also integrated into the hearing aid housing 1.
For the purpose of accepting external audio signals, a so-called audio shoe is used in many cases for hearing aids. The audio shoe is affixed to the hearing aid so that the audio signals are transmitted from the audio shoe to the hearing aid by means of electrical contacts. Various methods have become established for affixing an audio shoe to the housing of a hearing aid. Under one method which originated from the applicant, the audio shoe is twisted onto the housing of the hearing aid with a rotational movement. However, there are also audio shoes which are plugged onto the hearing aid either from the side or into its axis, by a linear movement.
A hearing aid module is known, from the publication DE 10 2005 061 795 A1, which can be affixed mechanically and electrically by an electromechanical interface to a multi-purpose interface on a hearing aid. The interface can be made in such a form that the hearing aid module can be put onto the hearing aid via a rail-type guide.
From the publication US 2006/0034474 A1, a hearing aid is known to which can be affixed an adapter, and via this a supplementary device. The supplementary device can be affixed to the adapter via a rail-type connection, whereby for example an electrical connection can also be established, via contact areas (pads), at the same time as the mechanical one.